Piano-lock



NATHANIEL VILTON, 0F BOSTON, MASSACHUSETTS.

PIANO-LOCK.

Specification Vof Letters Patent No. 19,529; dated March 2, 18%58.

To all whom t may concern.'

Be it known that I, NATHANIEL ViLToN, of Boston, in the county ofSuffolk and State of Massachusetts, have invented certain new and usefulImprovements in Piano-Locks, of which the following is a full, clear,and exact description, reference being had to the accompanying drawings,making part of this specication, in which- Figure l is a view of theinterior of a lock, the top plate being removed to show the partswithin, the bolt being withdrawn or unlocked. Fig. 2 is a view of thesame with the bolt shot.

My invention has reference to the improvement of that class of locksknown as piano locks which are usually employed where the lid of thearticle to be secured shuts down vertically upon the part to which thelock is attached, and to avoid having an unsightly hasp to shut into thelock, the

bolt is made to enter a recess or mortise in the edge of the lid. Thisrequires the bolt to have two motions, one upward or vertical to enterthe slot, and then one forward or horizontal to secure the lid byhooking over a plate set in the edge of the lid.

In the drawings A, is the case of the lock, the bolt a, is attached toand forms part of a bolt plate B, which slides upon the inner face ofthe case, being guided in its motions by certain pins and slots whichwill be described. The bolt plate B, has cut in it slots, l, 2, 3, and4, and a recess 5. From the case A, rise pins b, c, (Z, the pin b, beingreceived into the recess 5, when the bolt is shot as in Fig. 2. rlhepins c, and d, occupy the slots l and 2, which are of such a form thatas the plate B, is moved from the position of Fig. 1, it must first takea vertical and then a horizontal direction. In this latter movement thepin Z), entering the recess 5, steadies the upper part or bolt, and alsoholds it securely against any downward pressure that may be applied toit.

' the drawings.

Motion is given to the plate B, by the tumbler f, which has attached toits under side a pin z', that enters the slot 4 in the plate. A hub onthis tumbler passes through the case A, and receives a key or wrench.The plate B is cut away at 3, to accommodate this hub of the tumbler.The pin d, is carried up through the plate B, and serves as a pivot fora latch C, of the form shown in It is pressed down toward the tumbler f,by a spring g, which bears against the side of the case. When the boltis shot (Fig. 2) a notch 8 near the end of this latch catches a pin e,attached to the plate B, and secures the bolt frcmibeing forced orjarred back, as was liable to happen to most locks of this class withwhich I am acquainted. lVhen the lock is to be unlocked the tumbler f,lirst strikes upon a piece 7, of the latch and lifts it off the pin e,and then through the pin z', and slot L completes the movement of theplate B. The latch presses upon the pin e, when the plate is descendingvertically and assists the bolt to come home by the action of the springg. By thus raising the bolt vertically to its full height before itreceives its hori- Zontal movements, instead of giving it a diagonaldirection I am enabled to enter the bolt in a smaller recess 1n the lid,and to hold the lid down more firmly.

That I claim as my invention and desire to secure by Letters Patent isThe construction of the bolt plate B, with slots 1 and 2 of the formshown whereby said plate is guided in its two positive motions asdescribed, and actuating the said bolt directly by the key in itsmotions as set forth.

NATHL. `VVILTON.

lVitnesses':

Trios. R. RoAoH, THos. L. GLovER.

